1. Field of the Invention
The present invention relates to catalysts for olefin polymerization, methods for producing them, and methods for producing olefin polymers. More precisely, the invention relates to high-activity catalysts for olefin polymerization, to efficient methods for producing them, and to methods of using the olefin polymerization catalysts for efficiently producing high-quality olefin polymers.
2. Background Art
Recently, a method has been proposed of using a catalyst comprising a metallocene compound and an aluminoxane for polymerizing olefins in the presence of the catalyst to produce olefin polymers (Japanese Patent Laid-Open Nos. 19309/1983, 167307/1990). It is known that the polymerizing method of using such a catalyst is better than a method of using a conventional Ziegler-Natta catalyst that comprises a titanium or vanadium compound and an organic aluminium compound since the polymerization activity per the transition metal in the former is extremely high and since the former produces polymers having a narrow molecular weight distribution.
Another method has been proposed for polymerizing olefins in the presence of a catalyst that comprises catalytic components of a transition metal compound and an aluminoxane or organic aluminium compound as carried on an inorganic oxide such as silica, alumina or the like (Japanese Patent Laid-Open Nos. 108610/1986, 101303/1989).
However, in order that the methods noted above could have a satisfactory degree of polymerization activity, a large amount of an aluminoxane must be used therein. Therefore, in those methods, the activity per aluminium used is low, and the methods are uneconomical. In addition, since a large amount of aluminium remains in the polymers formed, the methods are further problematic in that the catalyst residue must be removed from the polymers formed therein.
Still another method has been proposed of using clay minerals as catalytic components (Japanese Patent Laid-Open Nos. 25214/1993, 301917/1993, 33814/1995). In this method, however, it is said that the clay minerals to be used must be pre-treated with organic aluminium compounds, especially with methylaluminoxane or trimethylaluminium which is extremely expensive and dangerous. In addition, the method is problematic in that the catalyst activity per aluminium therein is not satisfactory and the amount of the catalyst residue that may remain in the products is large.
In particular, the additional problem with the method of using such clay minerals is that aqueous suspensions of the clay minerals must be repeatedly pre-treated with magnesium chloride or the like and must be thereafter further treated with hydrochloric acid and then washed, and the treatment requires a lot of time.
The present invention has been made in consideration of the problems noted above, and its object is to provide catalysts for olefin polymerization capable of being prepared within a short period of time and to provide methods of using the catalysts for efficiently and inexpensively producing olefin polymers. Specifically, the catalysts do not require a large amount of methylaluminoxane or trimethylaluminium which has poor storage stability and is dangerous and which is therefore not easy to handle. In addition, in the methods of using the catalysts for olefin polymerization, since the amount of the organic aluminium compound to be used in the total polymerization system can be greatly reduced, the metal component that may remain in the polymers produced is much reduced. Therefore, the polymers produced in the methods do not require post-treatment. In particular, the catalysts are especially favorable to producing styrenic polymers having a stereospecifically-controlled syndiotactic structure.
The present invention encompasses three aspects, which are mentioned in detail hereinunder.
We, the present inventors have found that the object of the invention noted above can be attained by using a polymerization catalyst that comprises catalytic components having been specifically treated, and, on the basis of this finding, we have completed the first aspect of the invention.
Specifically, the first aspect of the invention is to provide a catalyst for olefin polymer production, a method for producing it, and a method of using it for producing olefin polymers, which are as follows:
1. A catalyst for olefin polymer production, which is obtained by contacting a product as prepared by contacting (A) clay, a clay mineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) water with each other, with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table.
2. A catalyst for olefin polymer production, which is obtained by contacting a product as prepared by contacting (A) clay, a clay mineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) water with each other, with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table and (E) an alkylating agent.
3. The catalyst for olefin polymer production of above 1 or 2, wherein the component (A), clay, a clay mineral or an ion-exchanging layered compound is selected from phyllosilicic acid compounds.
4. The catalyst for olefin polymer production of any one of above 1 to 3, wherein the component (B), an organic silane compound has at least one alkyl group directly bonded to the silicon atom of the compound.
5. The catalyst for olefin polymer production of any one of above 1 to 4, wherein the amount of the component (C), water is at least 1% by weight relative to the dry weight of the component (A).
6. The catalyst for olefin polymer production of any one of above 1 to 5, wherein the component (D), a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table has a ligand having a carbon-carbon unsaturated bonding group or a carbon-nitrogen unsaturated bonding group.
7. The catalyst for olefin polymer production of any one of above 1 to 6, wherein the component (D), a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table is represented by any of the following general formulae (I-1) to (I-4):
Q1a(C5H5xe2x88x92axe2x88x92bR1b) (C5H5xe2x88x92axe2x88x92cR2c)M1X1Y1xe2x80x83xe2x80x83(I-1)
Q2a(C5H5xe2x88x92axe2x88x92dR3d)Z1M1X1Y1xe2x80x83xe2x80x83(I-2)
(C5H5xe2x88x92eR4e)M1X1Y1W1xe2x80x83xe2x80x83(I-3)
L1L2M2X1Y1xe2x80x83xe2x80x83(I-4)
where Q1 represents a bonding group that crosslinks the two conjugated five-membered cyclic ligands (C5H5xe2x88x92axe2x88x92bR1b) and (C5H5xe2x88x92axe2x88x92cR2c);
Q2 represents a bonding group that crosslinks the conjugated five-membered cyclic ligand (C5H5xe2x88x92axe2x88x92dR3d) and the group Z1;
R1, R2, R3 and R4 each represent a hydrocarbon group, a halogen atom, an alkoxy group, a silicon-containing hydrocarbon group, a phosphorus-containing hydrocarbon group, a nitrogen-containing hydrocarbon group, or a boron-containing hydrocarbon group; and a plurality of these groups, if any, may be the same or different, and may be bonded to each other to form a cyclic structure;
a represents 0, 1 or 2;
b, c and d each represent an integer of from 0 to 5 when a=0, or an integer of from 0 to 4 when a=1, or an integer of from 0 to 3 when a=2;
e represents an integer of from 0 to 5;
M1 represents a transition metal of Groups 4 to 6 of the Periodic Table;
M2 represents a transition metal of Groups 8 to 10 of the Periodic Table;
L1 and L2 each represent a coordination-bonding ligand;
X1, Y1, Z1 and W1 each represent a covalent-bonding or ionic-bonding ligand; and
L1, L2, X1, Y1 and W1 may be bonded to each other to form a cyclic structure.
8. The catalyst for olefin polymer production of any one of above 2 to 7, wherein the component (E), an alkylating agent is an organic aluminium compound.
9. A method for producing a catalyst for olefin polymer production, which comprises contacting (A) clay, a claymineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) at least 1% by weight, relative to the dry weight of the component (A), of water with each other, followed by further contacting the resulting product with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table.
10. A method for producing a catalyst for olefin polymer production, which comprises contacting (A) clay, a clay mineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) at least 1% by weight, relative to the dry weight of the component (A), of water with each other, followed by further contacting the resulting product with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table and (E) an alkylating agent.
11. The method for producing a catalyst for olefin polymerization of above 9, wherein the step of contacting (A) clay, a clay mineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) at least 1% by weight, relative to the dry weight of the component (A), of water with each other, followed by further contacting the resulting product with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table is effected in an anhydrous aprotic solvent.
12. The method for producing a catalyst for olefin polymerization of above 10, wherein the step of contacting (A) clay, a clay mineral or an ion-exchanging layered compound, (B) an organic silane compound and (C) at least 1% by weight, relative to the dry weight of the component (A), of water with each other, followed by further contacting the resulting product with (D) a transition metal complex containing a transition metal of Groups 4 to 6 or Groups 8 to 10 of the Periodic Table and (E) an alkylating agent is effected in an anhydrous aprotic solvent.
13. A method for producing olefin polymers, for which is used the catalyst for olefin polymer production of any one of above 1 to 8.
We, the inventors have further found that the object of the invention can be attained by a method of producing a catalyst for olefin polymerization from a transition metal compound and a silane compound-processed clay, which comprises contacting a transition metal compound with a silane compound-processed clay as prepared by contacting an aqueous dispersion of water-swellable clay with a silane compound, and, on the basis of this finding, we have completed the second aspect of the invention.
Specifically, the second aspect of the invention is to provide the following:
1. A method of producing a catalyst for olefin polymerization from a transition metal compound and a silane compound-processed clay, which comprises contacting a transition metal compound with a silane compound-processed clay as prepared by contacting a clay dispersion of water-swellable clay in water with a silane compound.
2. The method of producing a catalyst for olefin polymerization of above 1, wherein the water-swellable clay is a phyllosilicate.
3. The method of producing a catalyst for olefin polymerization of above 1, wherein the water-swellable clay is of the smectite family or the mica family.
4. The method of producing a catalyst for olefin polymerization of above 1, wherein the water-swellable clay is an alkali metal or alkaline earth metal salt of montmorillonite.
5. The method of producing a catalyst for olefin polymerization of any one of above 1 to 4, wherein a clay dispersion as prepared by dispersing water-swellable clay in water of at least 40 times by weight the clay is contacted with a silane compound.
6. The method of producing a catalyst for olefin polymerization of any one of above 1 to 5, wherein the silane compound is represented by a general formula (II-1):
(R)nxe2x80x94Sixe2x80x94X(4xe2x88x92n)xe2x80x83xe2x80x83(II-1)
where R represents a substituent of which the atom in the site directly bonding to the silicon atom is a carbon, silicon or hydrogen atom; X represents a substituent of which the atom in the site directly bonding to the silicon atom is a halogen, oxygen or nitrogen atom; plural R""s and X""s, if any, may be the same or different ones, respectively; and n represents 0 or an integer of from 1 to 4.
7. The method of producing a catalyst for olefin polymerization of any one of above 1 to 5, wherein the silane compound is represented by a general formula (II-2):
(R)mxe2x80x94Sixe2x80x94X(4xe2x88x92m)xe2x80x83xe2x80x83(II-2)
where R represents a substituent of which the atom in the site directly bonding to the silicon atom is a carbon, silicon or hydrogen atom; X represents a substituent of which the atom in the site directly bonding to the silicon atom is a halogen, oxygen or nitrogen atom; plural R""s and X""s, if any, may be the same or different ones, respectively; and m represents an integer of from 1 to 3.
8. The method of producing a catalyst for olefin polymerization of any one of above 1 to 7, wherein the transition metal compound is a complex of a transition metal of Groups 4 to 6 of the Periodic Table having a conjugated five-membered ring as the ligand, or a complex of a transition metal of Groups 8 to 10 of the Periodic Table having an organic ligand as bonded to the transition metal via a nitrogen or phosphorus atom therebetween.
9. The method of producing a catalyst for olefin polymerization of any one of above 1 to 8, wherein the components are further contacted with an organic metal compound with a metal of Groups 1, 2, 13 and 14 of the Periodic Table.
10. A catalyst for olefin polymerization, which is produced according to the method of any one of above 1 to 9.
11. A method for producing olefin polymers, wherein olefins are polymerized in the presence of the catalyst for olefin polymerization of above 10.
We, the inventors have still further found that the object of the invention can be attained by a catalyst for olefin polymerization, which comprises a transition metal compound and a silane compound-processed clay that gives absorption peaks in a specific wavelength range in infrared absorption spectrometry, and, on the basis of this finding, we have completed the third aspect of the invention.
Specifically, the third aspect of the invention is to provide the following:
1. A catalyst for olefin polymerization, which comprises a transition metal compound and a silane compound-processed clay that gives absorption peaks in a range falling between 1090 and 1050 cmxe2x88x921 and/or in a range falling between 1015 and 995 cmxe2x88x921 in infrared absorption spectrometry.
2. The catalyst for olefin polymerization of above 1, wherein the silane compound-processed clay is prepared by processing a phyllosilicate with a silane compound.
3. The catalyst for olefin polymerization of above 1 or 2, wherein the silane compound-processed clay is prepared by processing a mineral of the smectite family or a compound having a smectite structure with a silane compound.
4. The catalyst for olefin polymerization of any one of above 1 to 3, wherein the silane compound-processed clay is prepared by processing montmorillonite with a silane compound.
5. The catalyst for olefin polymerization of any one of above 1 to 4, wherein the transition metal compound is a complex of a transition metal of Groups 4 to 6 of the Periodic Table having a conjugated five-membered ring as the ligand, or a complex of a transition metal of Groups 8 to 10 of the Periodic Table having an organic ligand as bonded to the transition metal via a nitrogen or phosphorus atom therebetween.
6. The catalyst for olefin polymerization of any one of above 1 to 5, which further contains an organic metal compound with a metal of Groups 1, 2, 13 and 14 of the Periodic Table.
7. A method for producing a catalyst for olefin polymerization, which comprises contacting a silane compound-processed clay with a transition metal compound and in which said silane compound-processed clay is prepared by contacting a silane compound of a general formula (III-1):
(R)nxe2x80x94Sixe2x80x94X(4xe2x88x92n)xe2x80x83xe2x80x83(III-1)
where R represents a substituent of which the atom in the site directly bonding to the silicon atom is a carbon, silicon or hydrogen atom; X represents a substituent of which the atom in the site directly bonding to the silicon atom is a halogen, oxygen or nitrogen atom; plural R""s and X""s, if any, may be the same or different ones, respectively; and n represents an integer of 2 or 3, with clay, and gives absorption peaks in a range between falling 1090 and 1050 cmxe2x88x921 and/or in a range falling between 1015 and 995 cmxe2x88x921 in infrared absorption spectrometry.
8. A method for producing olefin polymers, wherein olefins are polymerized in the presence of the catalyst for olefin polymerization of any one of above 1 to 6.
9. A method for producing olefin polymers, wherein olefins are polymerized in the presence of the catalyst for olefin polymerization as obtained according to the method of above 7.